anna.zhdan/session-resume

acp-model/api/acp-model.api

@@ -66,6 +66,10 @@ public final class com/agentclientprotocol/model/AcpMethod$AgentMethods$SessionP
 	public static final field INSTANCE Lcom/agentclientprotocol/model/AcpMethod$AgentMethods$SessionPrompt;
 }
 
+public final class com/agentclientprotocol/model/AcpMethod$AgentMethods$SessionResume : com/agentclientprotocol/model/AcpMethod$AcpSessionRequestResponseMethod {
+	public static final field INSTANCE Lcom/agentclientprotocol/model/AcpMethod$AgentMethods$SessionResume;
+}
+
 public final class com/agentclientprotocol/model/AcpMethod$AgentMethods$SessionSetMode : com/agentclientprotocol/model/AcpMethod$AcpSessionRequestResponseMethod {
 	public static final field INSTANCE Lcom/agentclientprotocol/model/AcpMethod$AgentMethods$SessionSetMode;
 }
@@ -2005,6 +2009,73 @@ public final class com/agentclientprotocol/model/ResourceLink$Companion {
 	public final fun serializer ()Lkotlinx/serialization/KSerializer;
 }
 
+public final class com/agentclientprotocol/model/ResumeSessionRequest : com/agentclientprotocol/model/AcpRequest, com/agentclientprotocol/model/AcpWithSessionId {
+	public static final field Companion Lcom/agentclientprotocol/model/ResumeSessionRequest$Companion;
+	public synthetic fun <init> (Ljava/lang/String;Ljava/lang/String;Ljava/util/List;Lkotlinx/serialization/json/JsonElement;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public synthetic fun <init> (Ljava/lang/String;Ljava/lang/String;Ljava/util/List;Lkotlinx/serialization/json/JsonElement;Lkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public final fun component1-7EW-EgU ()Ljava/lang/String;
+	public final fun component2 ()Ljava/lang/String;
+	public final fun component3 ()Ljava/util/List;
+	public final fun component4 ()Lkotlinx/serialization/json/JsonElement;
+	public final fun copy-wPMwmcM (Ljava/lang/String;Ljava/lang/String;Ljava/util/List;Lkotlinx/serialization/json/JsonElement;)Lcom/agentclientprotocol/model/ResumeSessionRequest;
+	public static synthetic fun copy-wPMwmcM$default (Lcom/agentclientprotocol/model/ResumeSessionRequest;Ljava/lang/String;Ljava/lang/String;Ljava/util/List;Lkotlinx/serialization/json/JsonElement;ILjava/lang/Object;)Lcom/agentclientprotocol/model/ResumeSessionRequest;
+	public fun equals (Ljava/lang/Object;)Z
+	public final fun getCwd ()Ljava/lang/String;
+	public final fun getMcpServers ()Ljava/util/List;
+	public fun getSessionId-7EW-EgU ()Ljava/lang/String;
+	public fun get_meta ()Lkotlinx/serialization/json/JsonElement;
+	public fun hashCode ()I
+	public fun toString ()Ljava/lang/String;
+}
+
+public final synthetic class com/agentclientprotocol/model/ResumeSessionRequest$$serializer : kotlinx/serialization/internal/GeneratedSerializer {
+	public static final field INSTANCE Lcom/agentclientprotocol/model/ResumeSessionRequest$$serializer;
+	public final fun childSerializers ()[Lkotlinx/serialization/KSerializer;
+	public final fun deserialize (Lkotlinx/serialization/encoding/Decoder;)Lcom/agentclientprotocol/model/ResumeSessionRequest;
+	public synthetic fun deserialize (Lkotlinx/serialization/encoding/Decoder;)Ljava/lang/Object;
+	public final fun getDescriptor ()Lkotlinx/serialization/descriptors/SerialDescriptor;
+	public final fun serialize (Lkotlinx/serialization/encoding/Encoder;Lcom/agentclientprotocol/model/ResumeSessionRequest;)V
+	public synthetic fun serialize (Lkotlinx/serialization/encoding/Encoder;Ljava/lang/Object;)V
+	public fun typeParametersSerializers ()[Lkotlinx/serialization/KSerializer;
+}
+
+public final class com/agentclientprotocol/model/ResumeSessionRequest$Companion {
+	public final fun serializer ()Lkotlinx/serialization/KSerializer;
+}
+
+public final class com/agentclientprotocol/model/ResumeSessionResponse : com/agentclientprotocol/model/AcpCreatedSessionResponse, com/agentclientprotocol/model/AcpResponse {
+	public static final field Companion Lcom/agentclientprotocol/model/ResumeSessionResponse$Companion;
+	public fun <init> ()V
+	public fun <init> (Lcom/agentclientprotocol/model/SessionModeState;Lcom/agentclientprotocol/model/SessionModelState;Lkotlinx/serialization/json/JsonElement;)V
+	public synthetic fun <init> (Lcom/agentclientprotocol/model/SessionModeState;Lcom/agentclientprotocol/model/SessionModelState;Lkotlinx/serialization/json/JsonElement;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public final fun component1 ()Lcom/agentclientprotocol/model/SessionModeState;
+	public final fun component2 ()Lcom/agentclientprotocol/model/SessionModelState;
+	public final fun component3 ()Lkotlinx/serialization/json/JsonElement;
+	public final fun copy (Lcom/agentclientprotocol/model/SessionModeState;Lcom/agentclientprotocol/model/SessionModelState;Lkotlinx/serialization/json/JsonElement;)Lcom/agentclientprotocol/model/ResumeSessionResponse;
+	public static synthetic fun copy$default (Lcom/agentclientprotocol/model/ResumeSessionResponse;Lcom/agentclientprotocol/model/SessionModeState;Lcom/agentclientprotocol/model/SessionModelState;Lkotlinx/serialization/json/JsonElement;ILjava/lang/Object;)Lcom/agentclientprotocol/model/ResumeSessionResponse;
+	public fun equals (Ljava/lang/Object;)Z
+	public fun getModels ()Lcom/agentclientprotocol/model/SessionModelState;
+	public fun getModes ()Lcom/agentclientprotocol/model/SessionModeState;
+	public fun get_meta ()Lkotlinx/serialization/json/JsonElement;
+	public fun hashCode ()I
+	public fun toString ()Ljava/lang/String;
+}
+
+public final synthetic class com/agentclientprotocol/model/ResumeSessionResponse$$serializer : kotlinx/serialization/internal/GeneratedSerializer {
+	public static final field INSTANCE Lcom/agentclientprotocol/model/ResumeSessionResponse$$serializer;
+	public final fun childSerializers ()[Lkotlinx/serialization/KSerializer;
+	public final fun deserialize (Lkotlinx/serialization/encoding/Decoder;)Lcom/agentclientprotocol/model/ResumeSessionResponse;
+	public synthetic fun deserialize (Lkotlinx/serialization/encoding/Decoder;)Ljava/lang/Object;
+	public final fun getDescriptor ()Lkotlinx/serialization/descriptors/SerialDescriptor;
+	public final fun serialize (Lkotlinx/serialization/encoding/Encoder;Lcom/agentclientprotocol/model/ResumeSessionResponse;)V
+	public synthetic fun serialize (Lkotlinx/serialization/encoding/Encoder;Ljava/lang/Object;)V
+	public fun typeParametersSerializers ()[Lkotlinx/serialization/KSerializer;
+}
+
+public final class com/agentclientprotocol/model/ResumeSessionResponse$Companion {
+	public final fun serializer ()Lkotlinx/serialization/KSerializer;
+}
+
 public final class com/agentclientprotocol/model/Role : java/lang/Enum {
 	public static final field ASSISTANT Lcom/agentclientprotocol/model/Role;
 	public static final field Companion Lcom/agentclientprotocol/model/Role$Companion;
@@ -2021,12 +2092,14 @@ public final class com/agentclientprotocol/model/Role$Companion {
 public final class com/agentclientprotocol/model/SessionCapabilities : com/agentclientprotocol/model/AcpWithMeta {
 	public static final field Companion Lcom/agentclientprotocol/model/SessionCapabilities$Companion;
 	public fun <init> ()V
-	public fun <init> (Lkotlinx/serialization/json/JsonElement;)V
-	public synthetic fun <init> (Lkotlinx/serialization/json/JsonElement;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
-	public final fun component1 ()Lkotlinx/serialization/json/JsonElement;
-	public final fun copy (Lkotlinx/serialization/json/JsonElement;)Lcom/agentclientprotocol/model/SessionCapabilities;
-	public static synthetic fun copy$default (Lcom/agentclientprotocol/model/SessionCapabilities;Lkotlinx/serialization/json/JsonElement;ILjava/lang/Object;)Lcom/agentclientprotocol/model/SessionCapabilities;
+	public fun <init> (ZLkotlinx/serialization/json/JsonElement;)V
+	public synthetic fun <init> (ZLkotlinx/serialization/json/JsonElement;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public final fun component1 ()Z
+	public final fun component2 ()Lkotlinx/serialization/json/JsonElement;
+	public final fun copy (ZLkotlinx/serialization/json/JsonElement;)Lcom/agentclientprotocol/model/SessionCapabilities;
+	public static synthetic fun copy$default (Lcom/agentclientprotocol/model/SessionCapabilities;ZLkotlinx/serialization/json/JsonElement;ILjava/lang/Object;)Lcom/agentclientprotocol/model/SessionCapabilities;
 	public fun equals (Ljava/lang/Object;)Z
+	public final fun getResume ()Z
 	public fun get_meta ()Lkotlinx/serialization/json/JsonElement;
 	public fun hashCode ()I
 	public fun toString ()Ljava/lang/String;

acp-model/src/commonMain/kotlin/com/agentclientprotocol/model/Capabilities.kt

@@ -68,6 +68,7 @@ public data class McpCapabilities(
  */
 @Serializable
 public data class SessionCapabilities(
+    @EncodeDefault val resume: Boolean = false,
     override val _meta: JsonElement? = null
 ) : AcpWithMeta
 

acp-model/src/commonMain/kotlin/com/agentclientprotocol/model/Methods.kt

@@ -46,6 +46,8 @@ public open class AcpMethod(public val methodName: MethodName) {
         public object Authenticate : AcpRequestResponseMethod<AuthenticateRequest, AuthenticateResponse>("authenticate", AuthenticateRequest.serializer(), AuthenticateResponse.serializer())
         public object SessionNew : AcpRequestResponseMethod<NewSessionRequest, NewSessionResponse>("session/new", NewSessionRequest.serializer(), NewSessionResponse.serializer())
         public object SessionLoad : AcpRequestResponseMethod<LoadSessionRequest, LoadSessionResponse>("session/load", LoadSessionRequest.serializer(), LoadSessionResponse.serializer())
+        @UnstableApi
+        public object SessionResume : AcpSessionRequestResponseMethod<ResumeSessionRequest, ResumeSessionResponse>("session/resume", ResumeSessionRequest.serializer(), ResumeSessionResponse.serializer())
 
         // session specific
         public object SessionPrompt : AcpSessionRequestResponseMethod<PromptRequest, PromptResponse>("session/prompt", PromptRequest.serializer(), PromptResponse.serializer())

acp-model/src/commonMain/kotlin/com/agentclientprotocol/model/Requests.kt

@@ -211,6 +211,27 @@ public data class LoadSessionRequest(
     override val _meta: JsonElement? = null
 ) : AcpRequest, AcpWithSessionId
 
+/**
+ * **UNSTABLE**
+ *
+ * This capability is not part of the spec yet, and may be removed or changed at any point.
+ *
+ * Request parameters for resuming an existing session.
+ *
+ * Resumes an existing session without returning previous messages (unlike `session/load`).
+ * This is useful for agents that can resume sessions but don't implement full session loading.
+ *
+ * Only available if the Agent supports the `session.resume` capability.
+ */
+@UnstableApi
+@Serializable
+public data class ResumeSessionRequest(
+    override val sessionId: SessionId,
+    val cwd: String,
+    val mcpServers: List<McpServer>,
+    override val _meta: JsonElement? = null
+) : AcpRequest, AcpWithSessionId
+
 /**
  * Request parameters for sending a user prompt to the agent.
  *
@@ -398,6 +419,21 @@ public data class LoadSessionResponse(
     override val _meta: JsonElement? = null
 ) : AcpCreatedSessionResponse, AcpResponse
 
+/**
+ * **UNSTABLE**
+ *
+ * This capability is not part of the spec yet, and may be removed or changed at any point.
+ *
+ * Response from resuming an existing session.
+ */
+@UnstableApi
+@Serializable
+public data class ResumeSessionResponse(
+    override val modes: SessionModeState? = null,
+    override val models: SessionModelState? = null,
+    override val _meta: JsonElement? = null
+) : AcpCreatedSessionResponse, AcpResponse
+
 /**
  * Response containing the contents of a text file.
  */

acp/api/acp.api

@@ -73,10 +73,13 @@ public abstract interface class com/agentclientprotocol/agent/AgentSupport {
 	public abstract fun createSession (Lcom/agentclientprotocol/common/SessionCreationParameters;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 	public abstract fun initialize (Lcom/agentclientprotocol/client/ClientInfo;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 	public abstract fun loadSession-nk3TnMc (Ljava/lang/String;Lcom/agentclientprotocol/common/SessionCreationParameters;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
+	public fun resumeSession-nk3TnMc (Ljava/lang/String;Lcom/agentclientprotocol/common/SessionCreationParameters;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
+	public static synthetic fun resumeSession-nk3TnMc$suspendImpl (Lcom/agentclientprotocol/agent/AgentSupport;Ljava/lang/String;Lcom/agentclientprotocol/common/SessionCreationParameters;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 }
 
 public final class com/agentclientprotocol/agent/AgentSupport$DefaultImpls {
 	public static fun authenticate-fMnwWJU (Lcom/agentclientprotocol/agent/AgentSupport;Ljava/lang/String;Lkotlinx/serialization/json/JsonElement;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
+	public static fun resumeSession-nk3TnMc (Lcom/agentclientprotocol/agent/AgentSupport;Ljava/lang/String;Lcom/agentclientprotocol/common/SessionCreationParameters;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 }
 
 public final class com/agentclientprotocol/client/Client {
@@ -91,6 +94,7 @@ public final class com/agentclientprotocol/client/Client {
 	public static synthetic fun initialize$default (Lcom/agentclientprotocol/client/Client;Lcom/agentclientprotocol/client/ClientInfo;Lkotlinx/serialization/json/JsonElement;Lkotlin/coroutines/Continuation;ILjava/lang/Object;)Ljava/lang/Object;
 	public final fun loadSession-wPMwmcM (Ljava/lang/String;Lcom/agentclientprotocol/common/SessionCreationParameters;Lcom/agentclientprotocol/client/ClientOperationsFactory;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 	public final fun newSession (Lcom/agentclientprotocol/common/SessionCreationParameters;Lcom/agentclientprotocol/client/ClientOperationsFactory;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
+	public final fun resumeSession-wPMwmcM (Ljava/lang/String;Lcom/agentclientprotocol/common/SessionCreationParameters;Lcom/agentclientprotocol/client/ClientOperationsFactory;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 }
 
 public final class com/agentclientprotocol/client/ClientInfo {

acp/src/commonMain/kotlin/com/agentclientprotocol/agent/Agent.kt

@@ -153,6 +153,16 @@ public class Agent(
                 models = session.asModelState()
             )
         }
+
+        protocol.setRequestHandler(AcpMethod.AgentMethods.SessionResume) { params: ResumeSessionRequest ->
+            val sessionParameters = SessionCreationParameters(params.cwd, params.mcpServers, params._meta)
+            val session = createSession(sessionParameters) { agentSupport.resumeSession(params.sessionId, sessionParameters) }
+            return@setRequestHandler ResumeSessionResponse(
+                modes = session.asModeState(),
+                models = session.asModelState()
+            )
+        }
+
         protocol.setRequestHandler(AcpMethod.AgentMethods.SessionSetMode) { params: SetSessionModeRequest ->
             val session = getSessionOrThrow(params.sessionId)
             return@setRequestHandler session.executeWithSession {

acp/src/commonMain/kotlin/com/agentclientprotocol/agent/AgentSupport.kt

@@ -1,5 +1,6 @@
 package com.agentclientprotocol.agent
 
+import com.agentclientprotocol.annotations.UnstableApi
 import com.agentclientprotocol.client.ClientInfo
 import com.agentclientprotocol.common.SessionCreationParameters
 import com.agentclientprotocol.model.AuthMethodId
@@ -12,4 +13,18 @@ public interface AgentSupport {
     public suspend fun authenticate(methodId: AuthMethodId, _meta: JsonElement?): AuthenticateResponse = AuthenticateResponse()
     public suspend fun createSession(sessionParameters: SessionCreationParameters): AgentSession
     public suspend fun loadSession(sessionId: SessionId, sessionParameters: SessionCreationParameters): AgentSession
+
+    /**
+     * **UNSTABLE**
+     *
+     * This capability is not part of the spec yet, and may be removed or changed at any point.
+     *
+     * Resumes an existing session without returning previous messages.
+     *
+     * This method is only available if the agent advertises the `session.resume` capability.
+     */
+    @UnstableApi
+    public suspend fun resumeSession(sessionId: SessionId, sessionParameters: SessionCreationParameters): AgentSession {
+        throw NotImplementedError("Must be implemented by agent when advertising session.resume capability")
+    }
 }

acp/src/commonMain/kotlin/com/agentclientprotocol/client/Client.kt

@@ -201,6 +201,37 @@ public class Client(
         }
     }
 
+    /**
+     * **UNSTABLE**
+     *
+     * This capability is not part of the spec yet, and may be removed or changed at any point.
+     *
+     * Resume an existing session without returning previous messages.
+     *
+     * This method is only available if the agent advertises the `session.resume` capability.
+     *
+     * @param sessionId the id of the existing session to resume
+     * @param sessionParameters parameters for resuming the session
+     * @param operationsFactory a factory for creating [com.agentclientprotocol.common.ClientSessionOperations] for the session.
+     * A created object must also implement the necessary interfaces in the case when the client declares extra capabilities like file system or terminal support.
+     * See [ClientOperationsFactory.createClientOperations] for more details.
+     * @return a [ClientSession] instance for the resumed session
+     */
+    public suspend fun resumeSession(sessionId: SessionId, sessionParameters: SessionCreationParameters, operationsFactory: ClientOperationsFactory): ClientSession {
+        return withInitializingSession {
+            val resumeSessionResponse = AcpMethod.AgentMethods.SessionResume(
+                protocol,
+                ResumeSessionRequest(
+                    sessionId,
+                    sessionParameters.cwd,
+                    sessionParameters.mcpServers,
+                    sessionParameters._meta
+                )
+            )
+            return@withInitializingSession createSession(sessionId, sessionParameters, resumeSessionResponse, operationsFactory)
+        }
+    }
+
     private suspend fun createSession(sessionId: SessionId, sessionParameters: SessionCreationParameters, sessionResponse: AcpCreatedSessionResponse, factory: ClientOperationsFactory): ClientSession {
         val sessionDeferred = CompletableDeferred<ClientSessionImpl>()
         return runCatching {

build.gradle.kts

@@ -7,7 +7,7 @@ plugins {
 private val buildNumber: String? = System.getenv("GITHUB_RUN_NUMBER")
 private val isReleasePublication = System.getenv("RELEASE_PUBLICATION")?.toBoolean() ?: false
 
-private val baseVersion = "0.10.5"
+private val baseVersion = "0.11.0"
 
 allprojects {
     group = "com.agentclientprotocol"